The friend said, "Demi was belligerent, being slutty and doing coke all over the house.

"The guy who hosted the party shot multiple videos of this and what I’ve seen with my eyes, Demi is screaming, ‘ F*** ALL of you, I’m famous, I don’t care what any of you think of me the whole world loves me.’

"He shot her in the bathroom as she was finishing a line (of cocaine)."

It is the video that will rock Disney and one of its biggest stars and if released publicly, will stun millions of fans around the world.

In the footage, Lovato can be seen expertly snorting the crystalline narcotic up her nose through a rolled up dollar, according to the amateur cameraman who shot the startling imagery.